Title: Cogenerating and pre-annihilating dark matter by a new gauge interaction in a unified model

Here, grand unified theories based on large groups (with rank ≥ 6) are a natural context for dark matter models. They contain Standard-Model-singlet fermions that could be dark matter candidates, and can contain new non-abelian interactions whose sphalerons convert baryons, leptons, and dark matter into each other, ''cogenerating" a dark matter asymmetry comparable to the baryon asymmetry. In this paper it is shown that the same non-abelian interactions can ''pre-annihilate" the symmetric component of heavy dark matter particles χ, which then decay late into light stable dark matter particles ζ that inherit their asymmetry. We derive cosmological constraints on the parameters of such models. The mass of χ must be < 3000 TeV and their decays must happen when 2 × 10 –7 < T dec/mχ < 10 –4. It is shown that such decays can come from d=5 operators with coefficients of order 1/MGUT or 1/M Pℓ. We present a simple realization of our model based on the group SU(7).

Barr, S. M., and Scherrer, Robert J.. 2016.
"Cogenerating and pre-annihilating dark matter by a new gauge interaction in a unified model". United States.
doi:10.1088/1475-7516/2016/05/065. https://www.osti.gov/servlets/purl/1436124.

@article{osti_1436124,
title = {Cogenerating and pre-annihilating dark matter by a new gauge interaction in a unified model},
author = {Barr, S. M. and Scherrer, Robert J.},
abstractNote = {Here, grand unified theories based on large groups (with rank ≥ 6) are a natural context for dark matter models. They contain Standard-Model-singlet fermions that could be dark matter candidates, and can contain new non-abelian interactions whose sphalerons convert baryons, leptons, and dark matter into each other, ''cogenerating" a dark matter asymmetry comparable to the baryon asymmetry. In this paper it is shown that the same non-abelian interactions can ''pre-annihilate" the symmetric component of heavy dark matter particles χ, which then decay late into light stable dark matter particles ζ that inherit their asymmetry. We derive cosmological constraints on the parameters of such models. The mass of χ must be < 3000 TeV and their decays must happen when 2 × 10–7 < Tdec/mχ < 10–4. It is shown that such decays can come from d=5 operators with coefficients of order 1/MGUT or 1/MPℓ. We present a simple realization of our model based on the group SU(7).},
doi = {10.1088/1475-7516/2016/05/065},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 05,
volume = 2016,
place = {United States},
year = {2016},
month = {5}
}

Grand unified theories based on large groups (with rank ≥6) are a natural context for dark matter models. They contain Standard-Model-singlet fermions that could be dark matter candidates, and can contain new non-abelian interactions whose sphalerons convert baryons, leptons, and dark matter into each other, “cogenerating' a dark matter asymmetry comparable to the baryon asymmetry. In this paper it is shown that the same non-abelian interactions can “pre-annihilate' the symmetric component of heavy dark matter particles χ, which then decay late into light stable dark matter particles ζ that inherit their asymmetry. We derive cosmological constraints on the parameters ofmore » such models. The mass of χ must be <3000 TeV and their decays must happen when 2×10{sup −7}« less

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